JP7762545B2 - Oil-based cleansing cosmetics - Google Patents

Description

The present invention relates to an oil-based cleansing cosmetic.

In recent years, makeup cosmetics with excellent water and oil resistance have been developed, significantly improving the longevity of makeup. Consequently, a variety of cleansing cosmetics have been developed for washing away makeup, including oil-based cleansing cosmetics with strong cleansing power. For example, Patent Documents 1 and 2 disclose oil-based cleansing cosmetics that contain an oil thickener to prevent dripping. However, these cleansing cosmetics can leave a strong sticky feeling after washing, and their viscosity can decrease with rubbing, leaving the problem of dripping unresolved.

Solidified oil-based cleansing cosmetics have therefore been developed to prevent dripping and improve usability (see, for example, Patent Documents 3 and 4). These oil-based cleansing cosmetics are characterized by the fact that liquid oil is encapsulated within solid oil crystals. When such oil-based cleansing cosmetics are applied to the skin, the solid oil crystals break down, causing the encapsulated liquid oil to seep out. The encapsulated liquid oil enables cleansing. However, with conventional solid oil-based cleansing cosmetics, the crystals are difficult to break down, and the rubbing action during use is easily transmitted directly to the skin, causing a strong sense of strain or irritation to the skin.

Japanese Patent Application Laid-Open No. 2000-136114 Japanese Patent Application Laid-Open No. 2005-194290 JP 2012-206974 A Japanese Patent Application Laid-Open No. 2001-213726

In light of the above circumstances, the present invention aims to provide a solid oil-based cleansing cosmetic that, when applied directly to the skin, not only has good cleansing power but also good hardness, i.e., good hardness and a pleasant feel on the skin, and also has excellent high-temperature stability.

In one embodiment of the present invention, the inventors discovered that an oil-based cleansing cosmetic of a specific hardness is created by combining two types of solid hydrocarbon waxes with different penetration strengths, a specific hydrocarbon oil and ester oil, and a specific nonionic surfactant. This oil-based cleansing cosmetic has a moderate hardness when spread on the skin at room temperature, is easy to use, and has excellent high-temperature stability, while also blending well with makeup cosmetics, removing dirt well, and providing a pleasant feel after cleansing. This discovery led to the completion of the present invention.

The present invention relates to an oil-based cleansing cosmetic composition containing the following (A), (B), (C), (D), and (E), wherein the cosmetic composition has a hardness of 50 to 150 g at 25°C measured with a 3 mmφ pressure-sensitive shaft:
(A) 7 to 20% by mass of a solid hydrocarbon wax having a penetration of 6 to 20 at 25°C
(B) 1 to 5% by mass of a solid hydrocarbon wax having a penetration of 25 to 50 at 25°C
(C) 25% by mass or less of a hydrocarbon oil that is liquid at 25°C (D) 50 to 90% by mass of an ester oil
(E) Nonionic surfactant having an HLB value of 3 to 14: 10 to 30% by mass

In the present invention, the mass ratio of component (D) to the total amount of (A) and (B) may be (D)/((A)+(B))=2.5 to 5, or the mass ratio of (D) to the total amount of (A), (B), and (C) may be (D)/((A)+(B)+(C))=2.5 to 5.

In the present invention, the oil-based cleansing cosmetic may be in a solid or stick form.

When the oil-based cleansing cosmetic of the present invention is applied directly to the skin, it not only has good cleansing power but also good hardness, i.e., good hardness and a good feel on the skin, and also has excellent high-temperature stability.

In this specification, "good cleansing power" means satisfying three criteria: compatibility with makeup, removal of dirt, and rinsability when washed off.

"Good hardness" means that when an oil-based cleansing cosmetic is spread on the skin under a certain load, it adheres to the skin while retaining its original shape. Specifically, this means that the cosmetic has a physical property of 50 to 150 g hardness measured with a 3 mm diameter pressure-sensitive shaft at 25°C, and provides a good feel on the skin in sensory evaluation.

In addition, "high temperature stability" means that the contents will not separate, shrink, crack, become oily (sweating), or undergo other changes in appearance when temperatures are high, such as in summer.

<Component (A)>
The component (A) used in the present invention is a solid hydrocarbon wax having a needle penetration at 25° C. of 6 to 20, preferably 7 to 15, and more preferably 7 to 12. Component (A) is used for the purpose of solidifying liquid oil to an appropriate hardness and maintaining the solid form; if the needle penetration is 6 or more, the liquid oil will have good solidification properties, and if it is 20 or less, the solidified liquid oil will ooze out, resulting in a good cleansing effect.

In the present invention, the penetration depth is measured by measuring the length of penetration of a specified needle (needle mass 2.5±0.02 g, needle holder mass 47.5±0.02 g, weight mass 50±0.05 g) into a wax sample maintained at 25±0.1°C in 5 seconds, and then multiplying this penetration distance (mm) by 10 to obtain the penetration depth. This value is measured in accordance with JIS K-2235-5.4 (1991).

A solid refers to a substance that is solid at 25°C and has a melting point of 65°C or higher, preferably 70°C or higher. Component (A) preferably has a melting point of 65-95°C, more preferably 70-85°C. A melting point of 65°C or higher provides good hardness retention, while a melting point of 95°C or lower provides good compatibility with makeup stains.

In the present invention, the melting point is measured according to Method 3 of the General Testing Methods in the Standards for Cosmetic Ingredients. Specifically, the sample is gradually heated to 90-92°C while stirring until melted, then the heating is stopped and the sample is allowed to cool to a temperature 8-10°C above the melting point. Next, a thermometer (a petrolatum melting point thermometer specified in Japanese Industrial Standards B7410) is cooled to 5°C, and after wiping off any moisture with filter paper, half of the mercury bulb is inserted into the sample, immediately removed, and allowed to cool vertically. When the adhering sample becomes cloudy, the sample is immersed in water at a temperature of 16°C or less for 5 minutes. The thermometer is then inserted into a test tube and secured with a cork so that the distance between the bottom of the thermometer and the bottom of the test tube is 15 mm. The test tube is then placed in a 500 mL beaker containing water at approximately 16°C, with the bottom of the test tube secured at a distance of 15 mm from the bottom of the beaker, and heated at a rate of 2°C per minute until the bath temperature reaches 30°C. Next, continue heating at a rate of 1°C per minute, and measure the temperature when a drop of the sample separates from the thermometer. This test is carried out three times, and if the difference in the measured values is less than 1°C, the average is taken. If the difference is 1°C or more, measure five times and take the average, which is the melting point.

Examples of solid hydrocarbon waxes with a penetration of 6 to 20 at 25°C for component (A) include mineral waxes such as ozokerite and ceresin; petroleum waxes such as paraffin and petrolatum; and synthetic hydrocarbons such as Fischer-Tropsch wax and polyethylene wax. Of these, ceresin, paraffin, and polyethylene wax are preferred, with paraffin being more preferred.

These waxes can be commercially available products, such as ceresin, Ceresin #810, Ceresin B (both manufactured by Nikko Rica Corporation); paraffin, Paraffin Wax 125, 130, 135, 140, 150, 155, HNP-3, 9, SP-0145, 0160, 0165, 1039, 3035, 3040 (manufactured by Nippon Seiro Co., Ltd.); Fischer-Tropsch wax, FT-0070, 0165 (manufactured by Nippon Seiro Co., Ltd.); polyethylene wax, PERFORMALENE PL POLYETHYLENE, PERFORMALENE 400, 500 (manufactured by New Phase Technologies Co., Ltd.).

Component (A) can be used alone or in combination with two or more types. From the viewpoint of good hardness and high-temperature stability, the content is 7 to 20% by mass of the total composition, preferably 8 to 18% by mass, and more preferably 10 to 16% by mass. If the blending amount is 7% by mass or more, the liquid oil in the solid oil crystals will not seep out and high-temperature stability will be good. Furthermore, if the blending amount is 20% by mass or less, the solid oil crystals will easily crumble, the product will not feel hard when touching the skin, and it will be possible to apply it evenly.

<(B) component>
Component (B) is a solid hydrocarbon wax having a penetration at 25°C of 25 to 50, preferably 28 to 40. Component (B) is used for the purpose of solidifying liquid oil to an appropriate hardness and maintaining the solid form; if the penetration is 25 or more, the liquid oil will have good solidification properties, and if it is 60 or less, the solidified liquid oil will ooze out, resulting in a good cleansing effect.

By combining component (A) with component (B), which have different penetration strengths, a stronger wax crystal structure is formed, achieving a balance between moldability, storage stability, and coatability.

Such waxes include microcrystalline wax and paraffin wax, with microcrystalline wax being preferred.

These waxes can be commercially available products. Examples of microcrystalline waxes include Multiwax W-445 (SONNEBORN), Hi-Mic-1045, 1070 (both manufactured by Nippon Seiro Co., Ltd.), and refined microcrystalline wax (manufactured by Nikko Rica Corporation).

Furthermore, the melting point of component (B) is preferably 65 to 95°C, and more preferably 70 to 85°C. If it is 65°C or higher, hardness retention is good, and if it is 95°C or lower, it will have good compatibility with makeup stains.

Component (B) can be used alone or in combination with two or more types. From the viewpoint of good hardness and high-temperature stability, the content is 1 to 5% by mass of the total composition, preferably 1.5 to 4.5% by mass, and more preferably 2 to 4% by mass. If the blending amount is 1% by mass or more, the liquid oil in the solid oil crystals will not seep out and high-temperature stability will be good. Furthermore, if the blending amount is 5% by mass or less, the solid oil crystals will easily crumble, the product will not feel hard when touching the skin, and it will be possible to apply it evenly.

<(C) component>
The hydrocarbon oil of component (C) used in the present invention is liquid at 25°C. Component (C) is used for the purposes of improving compatibility with makeup and reducing friction. Examples of such hydrocarbon oils include squalane, liquid paraffin, liquid isoparaffin, heavy liquid isoparaffin, polybutene, hydrogenated polyisobutene, and hydrogenated polydecene, with liquid paraffin, polybutene, and hydrogenated polyisobutene being preferred in terms of ease of application to the skin.

Component (C) can be used alone or in combination of two or more types. In terms of ease of application to the skin and compatibility with makeup cosmetics, the content is 25% by mass or less of the total composition, preferably 1 to 20% by mass, and more preferably 1.5 to 15% by mass. If the blending amount is 25% by mass or less, rinsability is good and no stickiness is felt after washing.

<(D) component>
The ester oil of component (D) used in the present invention is an ester oil having a viscosity of 100 mPa·s or less, preferably 1 to 60 mPa·s, at 25° C. Component (D) is used for the purpose of improving compatibility with makeup, and a viscosity of 100 mPa·s or less ensures good application to the skin and compatibility with makeup cosmetics.

In the present invention, viscosity was measured using a Brookfield rotational viscometer (Eiko Seiki Co., Ltd.: DV-1) at 25°C with rotor No. 1 at a rotation speed of 60 rpm for a rotation time of 30 seconds.

Such ester oils include, for example, vegetable oils such as jojoba oil, sunflower oil, linseed oil, and soybean oil; and fatty acid esters such as isopropyl myristate, octyldodecyl myristate, isopropyl isostearate, isononyl isononanoate, butyl stearate, isotridecyl isononanoate, ethylhexyl palmitate, cetyl ethylhexanoate, propylene carbonate, propylene glycol dicaprate, propanediol diisostearate, propanediol di(caprate/caprylate), glyceryl tri(caprylate/caprate), triethylhexanoin, and trimethylolpropane tri-2-ethylhexanoate. Of these, ethylhexyl palmitate, cetyl ethylhexanoate, and glyceryl tri(caprylate/caprate) are preferred.

Component (D) can be used alone or in combination of two or more types. From the viewpoint of ease of application to the skin and compatibility with makeup cosmetics, the content is 50 to 90% by mass of the total composition, preferably 50 to 80% by mass, and more preferably 50 to 70% by mass. A blend amount of 50% by mass or more will result in good compatibility with makeup cosmetics and good removal of makeup stains, while a blend amount of 90% by mass or less will result in good rinsing properties and no sticky feeling after rinsing.

<(E) component>
The nonionic surfactant of component (E) used in the present invention is intended to improve compatibility between the makeup cosmetic and the cleansing component and to facilitate washing. From the viewpoint of achieving both compatibility with the makeup cosmetic and solubility in water after rinsing, it is desirable to use one or a combination of two or more nonionic surfactants with an HLB value of 3 to 14. By combining multiple nonionic surfactants with different HLB values, it is possible to obtain well-balanced performance.

Nonionic surfactants are not particularly limited, but examples include glycerin fatty acid esters, polyglycerin fatty acid esters, sorbitan fatty acid esters, polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ethers, fatty acid polyoxyethylene glyceryl, polyether-modified silicone, and polyglycerin-modified silicone.

The "HLB (hydrophile-lipophile balance) value" referred to here was empirically derived by Griffin of Atlas Powder, Inc. in the United States, from emulsification tests using the company's own nonionic surfactants, and a formula has been proposed to express the relationship between this HLB value and the chemical structure of surfactants (see "New Cosmetics Handbook," Nikko Chemicals Co., Ltd., published October 30, 2006).

Examples of such nonionic surfactants include PEG-20 glyceryl triisostearate (HLB: 8.0), PEG-5 glyceryl triisostearate (HLB: 3.0), PEG-15 glyceryl oleate (HLB: 14.0), PEG-60 hydrogenated castor oil (HLB: 13.5), sorbeth-30 tetraoleate (HLB: 11.5), PEG-15 glyceryl stearate (HLB: 9.5), polyglycerol caprate (HLB: 9.5), and (C12-C14) Pareth-3 (HLB: 8.0). Among these, fatty acid polyoxyethylene glyceryl, and more particularly, polyoxyethylene glyceryl triisostearate having an ethylene oxide addition mole count of 10 to 30 moles, are more preferred.

Furthermore, from the viewpoint of ease of rinsing, the content of component (E) in the present invention is 10 to 30% by mass of the total composition, preferably 10 to 25% by mass, and more preferably 10 to 20% by mass. If the blending amount is 10% by mass or more, makeup stains are removed well, and if the blending amount is 30% by mass or less, there is no burden or irritation to the skin.

The oil-based cleansing cosmetic of the present invention has a hardness of 50 to 150 g, and more preferably 70 to 140 g, measured with a 3 mm diameter pressure-sensitive shaft at 25°C. Within this range, the cosmetic has a good feel on the skin at room temperature, excellent spreadability, little strain on the skin, and good high-temperature stability.

In this invention, "hardness" refers to the breaking load, expressed in grams, applied to a pressure-sensitive shaft when the diameter of the pressure-sensitive shaft is 3 mm and the sample stage is raised at a rate of 0.36 cm/sec using a Card Meter Max ME-305 manufactured by I-Techno Co., Ltd. at 25°C.

In the present invention, the mass ratio (D)/((A) + (B)) of component (D) to the total amount of components (A) and (B) is preferably 2.5 to 5, more preferably 2.5 to 4.8, from the viewpoints of ease of application to the skin, ease of blending with makeup cosmetics, and ease of rinsing.

In the present invention, the mass ratio (D)/((A) + (B) + (C)) of component (D) to the total amount of components (A), (B), and (C) is preferably 2.5 to 5, more preferably 2.5 to 4.5, from the viewpoints of ease of application to the skin, ease of blending with makeup cosmetics, and ease of rinsing.

The oil-based cleansing cosmetic of the present invention is a cleansing cosmetic that does not have fluidity at room temperature (25°C) and normal pressure (1 atmosphere), and its shape can be a rod, a plate, or one cast into a container. However, from the standpoint of ease of use, good moldability, and good spreadability, it is preferable that the oil-based cleansing cosmetic be filled into a stick container or the like, so that it can be applied directly to the skin without staining the hands.

Oily refers to a cosmetic that contains substantially no water, and the water content of the total cosmetic is preferably less than 3% by mass, more preferably less than 2% by mass, and even more preferably less than 1% by mass.

The oil-based cleansing cosmetic composition of the present invention may further contain an oil-based gelling agent, provided that the effects of the present invention are not impaired. Examples of oil-based gelling agents include those commonly used in cosmetics, such as metal soaps, organically modified clay minerals, and dextrin fatty acid esters.

In addition to the essential ingredients described above, the oil-based cleansing cosmetic of the present invention may contain powders, other oil thickeners, moisturizers, plant extracts, vitamins, antioxidants, preservatives, disinfectants, UV absorbers, anti-inflammatory agents, insect repellents, physiologically active ingredients, fragrances, essential oils, and other ingredients, provided that the purpose of the present invention is not impaired. Furthermore, these ingredients are not limited to their individual uses, and can be used for other purposes depending on the intended purpose. For example, vitamins can be used as antioxidants, or they can be used in combination with other purposes, for example, to achieve the effects of both an insect repellent and a fragrance.

The above-mentioned physiologically active ingredients include substances that impart some kind of physiological activity to the skin when applied to the skin. Examples include anti-inflammatory agents, anti-aging agents, UV protection agents, firming agents, antioxidants, moisturizing agents, blood circulation promoters, antibacterial agents, disinfectants, drying agents, cooling agents, warming agents, vitamins, amino acids, wound healing promoters, irritation soothing agents, analgesics, cell activators, enzyme components, etc. The above-mentioned physiologically active ingredients include natural plant extracts, seaweed extracts, herbal ingredients, and compounds, but of these, natural plant extracts, seaweed extracts, and herbal ingredients are particularly preferred from the standpoint of safety.

In addition to the above-mentioned natural plant extracts, seaweed extracts, and herbal ingredients, ingredients that can be used include, for example, biopolymers such as deoxyribonucleic acid, mucopolysaccharides, sodium hyaluronate, sodium chondroitin sulfate, collagen, elastin, chitin, chitosan, and hydrolyzed eggshell membrane; moisturizing ingredients such as amino acids, sodium lactate, urea, sodium pyrrolidone carboxylate, betaine, and whey; oily ingredients such as sphingolipids, ceramides, cholesterol, cholesterol derivatives, and phospholipids; anti-inflammatory agents such as ε-aminocaproic acid, glycyrrhizic acid, β-glycyrrhetinic acid, lysozyme chloride, guaiazulene, and hydrocortisone; vitamins (A, B2, B6, C, D, E), vitamins such as calcium pantothenate, biotin, nicotinamide, vitamin C ester, active ingredients such as allantoin, diisopropylamine dichloroacetate, 4-aminomethylcyclohexanecarboxylic acid, antioxidants such as tocopherol, carotenoids, flavonoids, tannins, lignans, saponin, cell activators such as alpha-hydroxy acids and beta-hydroxy acids, blood circulation promoters such as gamma-oryzanol and vitamin E derivatives, disinfectants such as isopropylmethylphenol, triclosan, hinokitiol, and benzalkonium chloride, cooling agents such as l-menthol and peppermint oil, and wound healing agents such as retinol and retinol derivatives.

The oil-based cleansing cosmetic of the present invention can be suitably used as a skin cleansing cosmetic, and can be used by applying it to the scalp, face, body, hands, feet, etc., rubbing it in to absorb dirt, and then wiping it off or rinsing with water.

Examples 1 to 4 and Comparative Examples 1 to 14
An oil-based cleansing cosmetic was prepared with the composition shown in Table 1, and its hardness was measured, and its high-temperature stability, compatibility with makeup cosmetics, makeup removal, and rinsing properties were evaluated. The results are also shown in Table 1. The present invention will be described in further detail with reference to examples, but the present invention is not limited to these examples in any way.

(Manufacturing method)
All of the ingredients shown in Table 1 were heated to 100°C to dissolve and mix uniformly to obtain a bulk oil-based cleansing cosmetic. The bulk was directly filled into a stick container at 80°C and cooled to solidify, yielding a stick-type oil-based cleansing cosmetic.

(Evaluation method)
(1) Hardness:
The measurement sample was prepared by heating the bulk to 100°C, dissolving it, mixing it uniformly, pouring it into a stick container, cooling it to 0°C to solidify it, and leaving it at 25°C for at least 2 hours. This sample was measured at 25°C using a Card Meter Max ME-305 manufactured by I-Techno Co., Ltd., with a pressure-sensitive shaft having a diameter of 3 mm and a spring weight of 200 g. The breaking load (unit: g) applied to the pressure-sensitive shaft when the sample stage was raised at a rate of 0.36 cm/sec was determined and used as the hardness.

(2) Feel on Skin A panel of 10 experts evaluated the ease of spreading when the oil-based cleansing cosmetics shown in Examples and Comparative Examples were used at room temperature, and evaluated the feel on skin according to the following criteria.
judgement
◎: Very easy to crumble, good spreadability, smooth feel when used. 〇: Slightly easy to crumble, good spreadability, almost no friction. △: Slightly hard to crumble, poor spreadability, frictional feel. ×: Very hard to crumble, poor spreadability, great frictional feel. -: A significant change was observed in the appearance.

(3) High temperature stability:
The oil-based cleansing cosmetic was filled into a stick container and stored in an upright position at 45°C. After two months had passed, the lid was opened and the contents were observed for any changes in appearance, such as separation, shrinkage, cracks, or sweating, and the stability was evaluated according to the following criteria.
judgement
〇: Almost no change in appearance is observed △: Cracks, sweating, etc. are observed ×: Major changes such as separation and shrinkage are observed

(4) Cleansing power test:
The compatibility with makeup cosmetics, makeup removal and rinsing properties were evaluated by the following sensory property test.
A panel of 10 experts evaluated the "compatibility with makeup cosmetics,""makeupremoval," and "rinsability" of the oil-based cleansing cosmetics shown in the Examples and Comparative Examples at room temperature according to the following criteria on a 5-point scale, and the average values (rounded to one decimal place) were expressed.
5-point rating
5 points: very good 4 points: good 3 points: average 2 points: slightly bad 1 point: bad

The results in Table 1 show that, compared to the comparative examples, the oil-based cleansing cosmetics of each example have a moderate hardness, are easy to use, and have excellent high-temperature stability, while also blending well with makeup cosmetics, are excellent at removing dirt, and have a pleasant feel after cleansing.

The following shows an example formulation for an oil-based cleansing cosmetic product according to the present invention.

Prescription Example 1
(Component name) (mass%)
1. Paraffin wax (penetration 12) 15.0
2. Microcrystalline wax (penetration 34) 3.0
3. Liquid paraffin 4.0
4. Ethylhexyl palmitate remaining 5. Caprylic/capric triglyceride 2.5
6. Cetyl ethylhexanoate 2.5
7. PEG-20 glyceryl triisostearate (HLB: 8.0) 15.0
8. Sorbeth-30 tetraoleate (HLB: 11.5) 3.0
9. Tocopherol 0.05
10. Lavender oil 0.015 11. Orange oil 0.02
12. Bergamot oil 0.015 13. Jojoba oil 0.001 14. Shea butter 0.001 15. Coloring (appropriate amount) 16. Phenoxyethanol 0.05

Prescription Example 2
(Component name) (mass%)
1. Paraffin wax (penetration 12) 11.0
2. Microcrystalline wax (penetration 34) 5.0
3. Liquid paraffin 4.0
4. Ethylhexyl palmitate remaining 5. Caprylic/capric triglyceride 2.5
6. Glyceryl behenate 0.5
7. Octadeca(behenate/hydroxystearic acid)polyglyceryl-20 1.0
8. PEG-20 glyceryl triisostearate (HLB: 8.0) 20.0
9. Tocopherol 0.05% 10. Carrot Oil 0.05% 11. Olive Juice Extract (trace amount) 12. Phenoxyethanol 0.05%

Claims (5)

An oil-based cleansing cosmetic comprising the following components (A), (B), (C), (D), and (E), wherein the cosmetic has a hardness of 50 to 150 g at 25°C measured with a 3 mmφ pressure-sensitive shaft.
(A) 7 to 20% by mass of paraffin wax having a penetration of 12 at 25°C
(B) 1 to 5% by mass of microcrystalline wax having a penetration of 34 at 25°C
(C) 25% by mass or less of a hydrocarbon oil that is liquid at 25°C (D) 50 to 90% by mass of an ester oil
(E) Nonionic surfactant having an HLB value of 3 to 14: 10 to 30% by mass The oil-based cleansing cosmetic according to claim 1, wherein the mass ratio of (D) to the total amount of (A) and (B) is (D)/((A)+(B))=2.5 to 5. The oil-based cleansing cosmetic according to claim 1 or 2, wherein the mass ratio of (D) to the total amount of (A), (B), and (C) is (D)/((A) + (B) + (C)) = 2.5 to 5. The oil-based cleansing cosmetic composition according to any one of claims 1 to 3, which is in a solid form. The oil-based cleansing cosmetic according to any one of claims 1 to 4, which is in a stick form.